In recent years, highly precise and fine image quality comparative to silver salt photography can be taken along with rapid progress of recording technology; therefore, ink-jet recording apparatuses for forming images using an ink-jet recording system have been widely used as image forming apparatuses.
Concerning these ink-jet recording apparatuses, there is a strong desire to further increase image forming speed while maintaining image quality thereof. However, in the case of performing image formation at high speed using an ink-jet recording apparatus, the recording medium will be discharged by passing through the pair of discharge rollers prior to the ink penetrating the recording medium such as paper, whereby the ink may adhere to the discharge rollers (offset). In this case, the ink having adhered to the discharge rollers will adhere to the recording medium, whereby an image defect may occur in the formed image.
In order to suppress the occurrence of offset, it has been considered to reduce the ejected amount of ink. However, in this case, it is difficult to form an image with a desired image density. Therefore, in order to suppress the occurrence of offset while forming an image with a desired image density, several compounds have been considered that can improve the permeability of the ink to the recording medium by being contained in the ink.
In view of this situation, as an ink excelling in the permeability to a recording medium (drying characteristic) and that can form a high quality image, an ink has been proposed that contains a compound in which a specific amount of ethylene oxide and/or propylene oxide has been added to a linear alkanol.
However, in order to form a high quality image, generally, for the dots formed by ink droplets landing the recording medium, it is desirable for the dot diameter to be sufficiently large, and the dot shape to be close to a perfect circle. However, with the above-mentioned ink containing the specific compound, since it is difficult to form dots having a shape close to a perfect circle, it is difficult to form high quality images.